Seiko 7B24 Manual page 47

・Howtoadjustthelengthoftheleatherband
With pressing buttons on both sides of the
1
buckle,pulltheleatherbandoutofthemoveable
loopandfixedloop.Thenopentheclasp.
Pullthepinoutofaadjustmentholeoftheband. 
3
Slide the band to adjust its length and find an
appropriatehole.Placethepinintothehole.
Press the push but tons again to
2
unfastenthebuckle.
Fasten the buckle with pressing the
4
pushbuttons.
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